/*
 * Copyright (c) 2004-2022, University of Oslo
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 * Redistributions of source code must retain the above copyright notice, this
 * list of conditions and the following disclaimer.
 *
 * Redistributions in binary form must reproduce the above copyright notice,
 * this list of conditions and the following disclaimer in the documentation
 * and/or other materials provided with the distribution.
 * Neither the name of the HISP project nor the names of its contributors may
 * be used to endorse or promote products derived from this software without
 * specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
package org.hisp.dhis.dxf2.metadata.objectbundle.validation;

import static java.util.Collections.emptyList;
import static org.hisp.dhis.dxf2.metadata.objectbundle.validation.ValidationUtils.createObjectReport;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.function.Consumer;
import java.util.stream.Collectors;
import org.hisp.dhis.common.IdentifiableObject;
import org.hisp.dhis.dxf2.metadata.objectbundle.ObjectBundle;
import org.hisp.dhis.feedback.ErrorCode;
import org.hisp.dhis.feedback.ErrorReport;
import org.hisp.dhis.feedback.ObjectReport;
import org.hisp.dhis.hibernate.HibernateProxyUtils;
import org.hisp.dhis.importexport.ImportStrategy;
import org.hisp.dhis.preheat.Preheat;
import org.hisp.dhis.preheat.PreheatIdentifier;
import org.hisp.dhis.schema.Property;
import org.hisp.dhis.schema.Schema;
import org.hisp.dhis.system.util.ReflectionUtils;
import org.springframework.stereotype.Component;

/**
 * @author Luciano Fiandesio
 */
@Component
public class UniquenessCheck implements ObjectValidationCheck {
  @Override
  public <T extends IdentifiableObject> void check(
      ObjectBundle bundle,
      Class<T> klass,
      List<T> persistedObjects,
      List<T> nonPersistedObjects,
      ImportStrategy importStrategy,
      ValidationContext ctx,
      Consumer<ObjectReport> addReports) {
    List<T> objects =
        selectObjectsBasedOnImportStrategy(persistedObjects, nonPersistedObjects, importStrategy);

    if (objects.isEmpty()) {
      return;
    }

    for (T object : objects) {
      List<ErrorReport> errorReports;

      errorReports =
          checkUniqueness(object, bundle.getPreheat(), bundle.getPreheatIdentifier(), ctx);

      if (!errorReports.isEmpty()) {
        addReports.accept(createObjectReport(errorReports, object, bundle));
        ctx.markForRemoval(object);
      }
    }
  }

  private List<ErrorReport> checkUniqueness(
      IdentifiableObject object,
      Preheat preheat,
      PreheatIdentifier identifier,
      ValidationContext ctx) {
    if (object == null || preheat.isDefault(object)) {
      return emptyList();
    }

    @SuppressWarnings("unchecked")
    Class<? extends IdentifiableObject> objType = HibernateProxyUtils.getRealClass(object);
    Map<String, Map<Object, String>> uniquenessMap =
        preheat.getUniquenessMap().computeIfAbsent(objType, key -> new HashMap<>());

    Schema schema = ctx.getSchemaService().getDynamicSchema(objType);
    List<Property> uniqueProperties =
        schema.getProperties().stream()
            .filter(p -> p.isPersisted() && p.isOwner() && p.isUnique() && p.isSimple())
            .collect(Collectors.toList());

    if (uniqueProperties.isEmpty()) {
      return emptyList();
    }
    return checkUniqueness(object, identifier, uniquenessMap, uniqueProperties);
  }

  private List<ErrorReport> checkUniqueness(
      IdentifiableObject object,
      PreheatIdentifier identifier,
      Map<String, Map<Object, String>> uniquenessMap,
      List<Property> uniqueProperties) {
    List<ErrorReport> errorReports = new ArrayList<>();
    uniqueProperties.forEach(
        property -> {
          Object value = ReflectionUtils.invokeMethod(object, property.getGetterMethod());

          if (value != null) {
            String objectIdentifier =
                uniquenessMap
                    .computeIfAbsent(property.getName(), key -> new HashMap<>())
                    .get(value);

            if (objectIdentifier != null) {
              if (!identifier.getIdentifier(object).equals(objectIdentifier)) {
                String identifiersWithName = identifier.getIdentifiersWithName(object);

                ErrorReport errorReport =
                    new ErrorReport(
                        HibernateProxyUtils.getRealClass(object),
                        ErrorCode.E5003,
                        property.getName(),
                        value,
                        identifiersWithName,
                        objectIdentifier);

                errorReports.add(
                    errorReport.setMainId(objectIdentifier).setErrorProperty(property.getName()));
              }
            } else {
              uniquenessMap.get(property.getName()).put(value, identifier.getIdentifier(object));
            }
          }
        });

    return errorReports;
  }
}
